Staybolt-machine



l. A. EDENA, In. sTAYsoL MACHINE.

APPLICATION HLD MAR. 6; 19|8..

Patented June 8, 1920.

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Br MM Ano/mfr J. A. EDEN, Jn.' sTAYBoLT MACHINE.

APPLICATION FILED MAR. 6. .1918.

1,342,534, Patented June 8, 1920.

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v @AnaB/ty UNITED STATES PAT'I OFFICE.

JAMES A. EDEN, JR., OF SPRINGFIELD, MASSACHUSETTS, ASSIGNOR TO WALTER I-I.

FOSTER, 0F NEW YORK, N. Y.

STAYBOLT-IVIACHINE.

Specification of Letters Patent.

Patented June 8, 1920.

Application filed March 6. 1918. Serial No. 220,718.

To all whom it may concern.'

Be it known that I, J AMES A. EDiiN; J r., a citizen of the United States, residing in Springfield, Massachusetts, have invented certain new and useful Improvements in Staybolt-Ylachines, of which the following is a specication.

i vertical section of a head for supporting the A which is suspended from a cross-head B to which is attached a strap running over a pulley C on a slowly driven shaft voverhead, the free end D of thestrap being within reach of theoperator so that he can lift the carriage by' pulling down the free end of the strap, the pulley C rotating in a direction to lift the carriage while the operator has only to hold the straptight on the pulley. A block or holder E is arranged on the ytable of the machine and hasl a.

squared hole F into which a squared end of the bolt blank is dropped. The carriage is lowered onto the top of the bolt and allowed to press thereon by its weight. The block- E is rotated while the cutters arev held.

' against rotation and the threads are cut and the intermediate part of the bolt turned down by means of dies and cutters which are brought into operation at suitable points.

Most stayboltsl are headless and have the threads at opposite ends of uniform diameter throughout. Special staybolts. however, are

required in particular locations which have their outer threaded ends tapered and I have illustrated such a bolt in Fig. 2 with an inner threaded end G of uniform diameter, an intermediate turned down portion H and an outer end which is threaded and of .uniform diameter over a portion J but of gradually enlarging diameter over the outer portion K. This bolt has a head L on which is a square proJection M used for'centering it in the block E of the machine, but usu- Y ally Y cut off after the bolt is set into the boiler. The present machine is designed for forming this special style of staybolt as well as the ordinary style.

The recessed block E which supports the lower end of the work is mounted on a shaft N gournaled in bearings in a casing O passing through an opening of somewhat larger diameter in the supporting plate P of the frame of the machine and carrying near its lower end a worm gear Q driven by a worm R on a shaft S which is rotated by any suitable means, and through which the overhead pulley C is also driven. The worm R is mounted in split bearings consisting of an extension T from the casing O and a cap U which is bolted to the extension T. This construction is advantageous in permitting the ready removal of the casing O withv its shaft N. The block or head E at the upper end being unscrewed and the bolt V which fastens the casing on the plate P being also removed, it is only necessary to remove the cap U of the worm, whereupon, by slightly tilting the casing O it can be lowered through the opening in the plate P for inspection and repair, if necessary.

Several styles of cutter heads are in use which include the threading dies and the turning cutters. In allV of them the operation is'substantially as follows. The cutter head in its upper position carries the dies closed and bearing on the top of the blank; therefore, as the blank turns the dies engage the work and cut a thread thereon from top to bottom. The turning tools are located in the same cutter head with the dies, at a point above the latter so that they follow' the dies down. In the initial position the cutters are opened or separated so that they do not touch the work. At a determined point in the downward travel of the head the cutters are closed or'pressed inward so as to commence the turning of the reduced clear of the work and the operator may lift the head quickly by the means above de- Y scribed and commence the making of a new' bolt.

The die head or cutter head illustrated is of a known type in which the dies and cutters are pivotally mounted on a plate W carried on the underside of the carriage A, around which plate W is a ring X mounted to turn and by its turning movement in one direction or the other to throw the dies and cutters inward or outward. Springs Y pull the rin X in the direction for opening the dies. n the outside of the ring X is mounted in adjustabley position a stop plate Z with a projection a adapted to be engaged by a pawl b pivotally mounted on the carriage A.

At the top of its movement a roller Yor on the ring X strikes a cam c (Fig. l) which throws the rin X around against the pull of its springs until the shoulder a catches under the pawl b, thus closing and locking the dies. At the lower end of the movement of the carriage the pawl b strikes a stop d, Fig. 1, and is lifted off the shoulder a, whereupon the springs turn the ring X in a direction to open the dies. The mechanism whereby the turning of the ring opens and closes the dies and holds them in the desired position is described hereinafter.

A point of improvement is in the means for producing at the bottom of lthe stroke a gradual turning of the ring and opening of the dies so that they will produce the tapered thread K, Fig. 2; and for regulating the rate of such taper. For this purpose the 4engaging face of the projection or shoulder a is made of such inclination that as the pawl b is gradually lifted there will be a small turning of the ring X in the direction of the arrow and thus a gradual separation of the thread cutting dies. The same result, of course, could be achieved by providing a tapered face for the pawl b and by variously shaping the engaging faces of the parts a and Z2. The stop Z is mounted in a bracket e, Fig. l, and held by a set screw 7, so that it can be adjusted in or out and will strike the pawl b at a point nearer to or farther from its pivot and will thus cause a slower or faster turning of the ring X and consequent regulation of the rate of taper of the thread.

It has been previously proposed to mount at a fixed point on the frame of the machine a wedge which would operate directly on the ring X so as to gradually turn the latter and cause a taper of the thread. But when a thread of different taper has been required a new wedge has had Vto be substituted. By the use of the pawl b and the adjustable stop d it becomes very easy to change the taper as required for different classes of work. The stop d might in fact be arranged so close to the pivot of the pawl I) as to lift the latter almost instantaneously and to stop the thread with practically no taper. l

For producing the Ordin-ary withdrawal of they dies, where the thread is not'to be tapered a die plate Z, Fig; 8, may be ksubstituted, having its projection a so shaped that there will be no movement until the pawl Z) entirely clears the projection.

The threading dies orchasers, of which one is indicated in section at g, F ig. 7, are mounted in blocks it supported by pivots y' from the plate W. Toggle links la are connectedat their outer ends to the ring X and at their inner ends to the blocks h and are set at Such an angle that they movement of the ring by the springs will ypull the dies away from the work indicated at K,; in Fig. 6, and the movement in. the oppositev direction will thrust the dies forcibly against the work. These links lo are set in thek lower parts of the ring X and blocks h so as to resist any tendency to tilt the blocks h by the`l backward reaction from the work. The construction is very simple andholds the dies firmly to the work and evenly throughout their length.

The meansr described for producing a ta-5 pered thread may be applied to the manufacture of' various other bolts than the staybolts specified, as also may the toggle arrangement for opening and closing the dies. In fact, the improvements generally are applicable to a variety of machines other than that illustrated and may be modified in detail and arrangement by persons skilled in the art without departing from the invention.

No claim is made to the toggle arrangement in the present application. Such an arrangement being shown with slight modifications in my application No. 271,631 and being claimed there.

l. A machine for threading staybolts or the like comprising a carriage, a die carrying head mounted thereon and havin a movable part which controls the opening of the dies and an adjustable stop adapted to strike said movable part at different points and thus to vary the rate of opening of the dies. f

2. A machine for threading staybolts or the like comprising a carriage, a die carryioo ing head mounted thereon having springactuated means for opening the dies and hav- 'ing a paWl which holds the dies closed and permits them to open gradually as the pavvl is Withdrawn and an adjustable stop adapted to engage said pavvl at different points to Withdraw it at diferent rates and to cause the gradual opening of the dies at different rates.

3. A machine for threading staybolts and the like including in combination a die carrying head having a spring actuated ring X which controls the adjustment of the dies a stop a on said ring and a pawl engaging said stop, the engaging faces of said stop and pawl being shaped to produce a gradual opening of the dies as the paWl is progressively Withdrawn.

4L. A machine for threading staybolts andthe like comprising a bolt carrier, a shaft N for the Same and a casing O carrying bearings in Which said shaft -is mounted, a worm gear on said shaft, a Worm engaging said gear and mounted in bearings comprising a projection from said casing and a movable cap, said casing O passing through an opening in a plate P so that by removal of said cap said casing, shaft and Worm gear y can be Withdrawn as a unit.

In Witness whereof, I have hereunto signed my name. v

JAMES A. EDEN, JR. 

